Horton



A. J. HORTON.

MOTOR CONTROLLER. APPLICATION FILED FEB. 10. 1917 Patented May 13, 1919..

2 SHEETSSHEET I.

A. I. HORTON. MOTOR CONTROLLER. APPLICATION FILED FEB. 10. 1911.

Patented May 13, 1919.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

ALBERT J. HORTON, or warm PLAINS, NEW YORK, AssIcNos TO THE CUTLER-HAMMER MFG 00., or MILWAUKEE, WISCONSIN, A CORPORATION or wIscoNsIN.

Moron-commoners.

Specification of Letters Patent.

PatentedMay 13, 1919.

Application filed February 10, 1917. Serial No. 147,788.

To all whom it may 00mm.-

Be it known that I, ALBERT-J. HORTON, a

citizen of the United States, residing at VVhitePlains, in the county of Westchester and State of New York, have invented new and useful Improvements in Motor-Controllers, of, which the following isa full,

It is frequently desired to effect substantial-ly synchronous operation of the driving motors of associated devices and it has heretofore beenproposed to secure such syn-- chronous operation by providing the motors with communicating devices cooperable to effect field regulation of one motor upon .variations in the relative speeds of the motors to thereby rectify such variations,- Further, it has been proposed in connection with this method to initially adjust the motors by field regulation thereof for approximately, the same speeds and while said method is in general quite satisfactory, much difficulty has been experienced due to the varying actions of the motors when starting one or both in a cold state. Also, difficulty has been experienced ineffecting promptness of response of the controlled motor to its regulating means without an abnormal ultimate variation of its field strength.

The present invention has among its obj ects to provide means for effecting substantially synchronous operation of a plurality of motors according to themethod mentioned which will overcome the foregoing difliculties. v

A further object is toprovide a regulating device operable manually or automatically for a gross regulatinge'fiect and thereafter operable automatically for a definite curtailment of the gross regulating effect thereof.

Other objects and advantages of the in vention will hereinafter appear.

The accompanying drawings illustrate one embodiment of the invention which will now be described, it being understood that the embodiment illustrated is susceptible of various modifications without departing from the scope of the appended claims.

In the'drawings,

Figure 1 is a diagrammatic view of the controller; and,

Figs. 2, 3 and 4 are detail views of the regulating device diagrammatically shown in Fig. 1; Referring to Fig. 1, the same shows two compound motors M and M each having an armature a, a scries'field winding 7 and a shunt field winding f. It is assumed that the motor M operates a leading machine and the motor M afollowing machine which it "is desired to synchronize with the former.

The details of control of the motor M are therefore not essential to an understanding of the invention and the motor has accordingly merely been shown as provided with a mainswitch 1, it being assumed that said motor operates at a substantially constant speed.

The motor M is shown as provided with a starting resistance r in series therewith and an electro-responsive switch 2 to short-circuit said resistance, said switch having its operating winding connected across the terminals ofthe' armature a for response at a given counter-voltage of said motor. Also, this motor is provided with an electromagnetically controlled field regulating rheostat R, a manually adjustable field rheostat R and a vibrating relay 3 for including said rheostats in circuit upon exclusion of the starting resistance 1 This relay is provided with two cumulative coils 3 and 3 both included in series with the motor M, the former permanently andthe latter initially included but subject to exclusion thereof with the starting resistance 1'. T he two coils insure closure of said relay for exclusion of all field resistance until the motor is accelerated by exclusion of resistance 1', whereupon-said relay is rendered effective to ac celerate the motor by alternate inclusion and exclusion of the field resistances according to current conditions in the armature circuit, in the usual manner. The rheostat R is provided for initial adjustment of the setting of the leading motor and as will be understood the same requires no further adjustment. T The. rheostat R'comprlses a centrally pivoted contact arm '4, one end thereof car-.

rying contact brushes 5 and 6 to sweep over series of contacts 7 and 8 respectivelyand the other end thereof carrying contact brushes 9 and 10 to sweep over series of contacts 11 and 12 respectively. The contacts 7- and 8 are arranged in a staggered relation and are respectively connected to .field resistances 1' and 1*, while the contacts 11 and 12 are similarly arranged and respectively connectedtofield resistancesr and The lowermost contacts- 7 and 8 are electrically connected and the uppermost contacts 11 and 12 are electrically connected whereby with tlie circuit connections hereinafter described the resistances a to r are in series and subject to gradual inclusion and exclusion by counter-clockwise and clockwise movements of" the contact-arm 4 respectively. Forefl'ecting such movements of the arm '4, operating solenoids 13 and 14 are provided, the former having its plunger 13 connected to said arm on the left hand side of its pivot by link 13 and the latter having its plunger 14 connected to said arm on the right hand. side of its pivot through a link 14". The solenoid 13 when energized thus provides for clockwise movement of thearm 4 'to gradually exclude the field r'esistances, while the solenoid 14 serves to move the. arm counter-clockwise to gradually include said resistances, said arm being shown in a position to include substantially one-half of the total .of said resistances. The

with a -double acting'dash'pot 18 to retard movementaof the arm 4' in both directions.

As diagrammatically shown, this dash pot is provided with a piston; rod '19 havinga lost motion connection wlth a right angle extension 4 of the arm 4 throughopposed springs 20 and 21. Thus with the arm 4 in any position the extension thereof being centered' between the springs, said armmaybe moved a given angular distance, for ex ample, over three contacts, independently of the dash pot and subject only to the opposi tion of the spring compressed thereby. On. the other hand, as soon as the angular move ment of the arm-4 exceeds therange mentioned, the dash pot acts to retard said arm until brought to rest. Then assuming de-- energizat'ion of both operating solenoids the compressed spring effects a return move- 'ment of said arm'equal to its initial movement independently of the dash pot, previ ously assumed to correspond to three contacts. Thus the rheostat is rendered substantially, quickly responsive through a given range to th initial pull of either operating solenoid Whereas it is thereafter subjected to dash-pot retardation andtoa bias for partial return movement when relieved of solenoid pull.

The automatic control means for-the solenoids 13 and 14-c'omprises electro-responsive relays 22 and 23 responsive to energize said solenoidsrespectively and in turn energizable selectively by switches 24 and 25 oper- The switch 24 is provided with twoi'setsof stationary contacts and with movable contact members. 24*. and 24? each adapted to bridge a pair of stationary contacts. These bridging contact members are slidably I mounted upon. a rod 24 and are biased apart by a spring interposed between the. same.

The rod 24 is biased to engage member 24 with'its stationary contacts'and is provided with shoulders above and below the memable respectively by the motors M and ,M. V

bers 24 and 24 to abut the same, said shoulders being so spaced that during upward movement of the rod 24 the member 24* reengages its stationary contacts prior to disengagement of member 24 with its stationary contacts.

The rod is operable by a cam 26 shown as fixed to-an extension of thetarmature shaft of motor M the contour of-said cam being such as to effect depression of the rod 24 once during each revolution of said armature but only for a relative short period. The switch 25 is shown as comprising a revoluble contact arm 25 con- A tinuously engaging a segment 25" and adapted to bridge said'segment with concentric segments 25", 25 and 25 Thearm 25 is shown as fixed to an extension ofithe armature shaft of motor M whereby it is. caused to make one complete revolution of said armature and during each revolution to engage'progresslvely the last three mentloned segments. It is, of course, to be understood that the switches 24 and -25 might be alike or ofother types than those 'illus- 'trated and might be operatively connected to the driven machines instead of to the motors and geared foranydesiredspeed ratlos. I i The arrangement'is suchv as to necessitate depression of switch 24 and engagement of contacts 25 and -25 of switch 25 to ener- 'gi zerelay23' for energization of solenoid 14 'and'to necessitate'depressionof. switch 24 and. engagement-of contacts 25 and 25 of .switchf25 to energize relay '22 forenergizationofsolenoid 13. Depression of switch 24 only during engagement of contacts 25" and 25 of switch 25. does not effect either relay and it is to be assumed that depression of the switch 24 is so timed as long as the motors operate in absolute synchronism.

Vhen, however, the motor M either lags vides for continued energization of the selected relay until said switch is again depressed and as will be understood, such depression of the switch 24 before correction of the speed of motor 1 by the'previously selected relay serves to reestablish the: energizing circuit of the same relay for prolongation of its regulative action. Accord- .ingly, with the rheostat construction described, energization of either solenoid 13 or 14 effects a quick. movement of the arm 4,

- unretarded by the dash pot,'through a given range previously assumed to be three buttons, and then through a further range of one or more buttons subject to dash-pot retardation, dependent upon the duration of energization of the selected solenoidL Then upon deenergization of the selected solenoid "the arm 4 returns through a range equal to three buttons, thus curtailing the gross speed adjustment accordingly, It will thus be ap parent that the rheostat provides for quick' response of the following motor M to meet the need of either quick acceleration or quick deceleration, whereas it effects an'ultimate regulation only to the extent of its net travel.

Considering now in further detail the circuit arrangement illustrated, current is supplied to both motors a-nd't-o the several electromagnetic devices-from a common circuit L, L, through a double pole switch 30, the

continuity of circuit of the two motors being shown for convenience as controlled by switch 1.. Motor M has its armature and series field connected directly across the sup- Iing 3 of relay 3, by conductors 33 and 34 through the winding 3? of said relay and thence through the armature and series field of said motor to and through'switch 1 to line L, while its shunt circuit extends from line L by conductors 31 and 35 through the resistance 1, rheostat arm 4 and resistance r by conductor 36 through resistance 1 This in turn elfects energization of relay 22 .or 23 rheostat arm 4and resistance 1 by conductor 3? through rheostat R, by conduc-' tor 38 through the shunt field winding of said motor to line L. However, immediately upon completion of the armature circuit as traced, the relay 3 is energized to short circuit both field rheostats, said short circuit extending from conductor 32 to and through said-relay to conductor 38 and thence di rectly to the shunt field windings. The Winding of switch 2 has one terminal thereof connected by conductor 40 to the right hand terminal of the armature of motor M and its oppo'site terminal connected by conductor 41 to the left hand terminal of said armature and upon response said switch 1 completes circuit from conductor 32 directly to conductor 34 thereby excluding the resistance r and relay coil 3. The relay is thus left with only its coil 3 included in circuit for the purpose set forth.

Assuming depression of switch 24,witli switch.25 in the position illustrated, circuit is established from line L by conductors 31, 35 and 43 through the down contact of switch 24, by conductor 44, to segment 25 of switch 25,"across arm 25 to segment 25,

by conductors 45 and 46 through the winding of relay 23, by conductors 47, 48 and 49 to and through the switch 1 to line L. This effects response of relay 23 which in closing establishes a circuit from line L by conductors 31, 35, 43 and 50 through said switch, by conductor 51 through 'switch 17, and thence through solenoid 14, by conductors 48 and 49 to and through switch 1 to line L. This efiects response of solenoid 14. Further assuming release of switch 24 but continued engagement of the same contacts of switch 25, the up contacts of switch 24 establish a maintaining circuit for relay 23 from conductor 43 through said contacts, by conductor 52 through a resistance 1" through auxiliary contacts 22 of relay 22, engaged in the open position of said relay, by conductor 53'directly to the winding'of relay 23.

This provides for continued energization of the relay and continued operation of the rheostat 4 by solenoid 14 until switch 24 is again depressed, whereupon said relay is deenergized to denergize solenoid 14. In this connection it'is to be noted that continued energization of relay 23 is also depending upon the relay 22 remaining in open position which insures against simultaneous closure of said relays.

Again assumingdepression of switch 24 but with the arm 25 of switch 25 in engagement with segment 25*, circuit is completed from line L to segment 25 as already traced, thence across arm 25 to segment 25 by conductor .54 through the winding of relay 22, by conductors 55, 48 and 49 to and through switch 1 to line L. This effects response of relay 22 which establishes circuit from line L by conductors 50 and 56 through switch 16, by conductor 57 through the winding of solenoid 13 to conductor 48 and thence to line L as already traced. Then assuming release of switch 24 during continued engagement of contacts and 25 of switch 25, the former switch establishes a maintaining circuit for relay 22 from line L to conductor 52 as already traced, thence througha resistance 1' and down contacts 23 of relay 23, which, are engaged in open position of said relay, by conductors 58 and 59 directly to the winding of relay 22. Thus the control of relay 22 is in all respects similar to the control above describedfor relay 23.

Furtherassuming depression of switch 24 with the arm 25*' of switch 25 in engage ment with segment 25, which as above stated occurs only when the two motors are in absolute synchronism, circuit is estab- .ment 25*, across. arm 25 to segment 25% through a lamp Z to. conductor 49 to and..

lished' from line L through switch 24 to segthrough switch 1 to line L. Thus energization of the lamp serves to indicate absolute synchronism of the two motors.

Referring now to Figs. 2 to 4, the same show the 'rheostat arm 4 as provided at opposite ends'w-ith contact holders 60 and 61 having sockets for the contacts 5, 6, 9 and 10, illustrated as of the pencil type, and with spring pressure devices 62, 63, 64 and' 65 respectively bearing upon said contacts to press the same into firm engagement with the series of contacts over which they slide.

. The holders 60 and 6l p'rovide for electrical connection for the two contacts carried by each and said holders are both insulated from said'arm to render said sets of contacts electrically independent. The series of stationary contacts 7, 8, 11 and 12 are mounted upon a suitable insulating base 66and the arm is centrally pivoted upon a stud 67 fixed to said base.

Also, the stud .67 has pivotally mounted thereon, in a position between said arm and I said base, a member 68, best illustrated in Fig. '4. This member is provided on the left hand side of its pivot with a link69 to connectthe same directly to the piston'of a double acting dashipo't, such as diagrammatically illustrated in' Fig..1. Also, this memberfis provided on-the opposite side of its pivot with opposed lugs 7 0' and 71 adapted to straddle a lug 72 on the arm 4, the former lugs being respectively provided with set screws 73 and74 to abut said lug 72 on opposite sides thereof.v These lugs.

thus provide a lost motion connection between the. rheostat arm and the dash-pot such as above described and the set screws 73- and 74 provide for adjustment .of the degree of such lost motion. Further, the member 68 is provided with a lug 75 protWeen the stud 67 and the right hand conjecting toward the arm 4 but positioned to clear the lug 72 on the latter and a spring 76 is coiled about the hub of said arm with' its extremities engaging both lugs 72 and 75 on opposite sides thereof. The spring is thus rendered double acting to center the arm 4 relatively to the member 68 and thus serves'the same purpose as the two springs .20.and 21 of the diagrammatic illustration,

Fig.1. In this connection it is to be noted 75 that since the spring 76 centers the arm 4 relatively to the'member 68, the lost motion between the arm .4 and dash pot is in effect divided into two ranges and that the set screws carried bythe .member 68 provide for adjustment of either range independently of the other.

The arm 4 is also provided with a'handle .77 by Which itmay be operated at will and with a pin 78 to operate the switchesl6'and 5 17 at their limits of movement. As shown lative tendency incidentto such operation.

2. The combination with aplurality of motors, of means to synchronize the same including speed regulating means for one op-' erable to different degrees and active automatically thereafter to curtailits regulative effect for difi'erent ultimate degrees of regu- 05 lation according to the degree of prior operation thereof. Q

3. The combination with a plurality of motors, of means to synchronize the same including speed regulating means'for one quickly responsive for a given degree. of regulation'and thereafter more slowly responsive for-a further degree of regulation, said regulating means being active autos matically after response to curtail its regulative tendency'incident to such response.

4. The combination-with a plurality .of motors, of means to synchronize the same 7 including adjustable speed regulating means for one quickly adjustable for a given degree of regulation and more slowly adjustable for subsequent. regulationto varying degrees, said regulating means tending upon all adjustment thereof to curtain its regulative-effect to a degree corresponding to that rasultingfrom .-said;-qu ick adjustment there-- 1 5. The combination with a plurality of motors, of regulating meansjfor one of said motors responsive upon a variation in the relative speeds of. said motors for rectifying such speed variation, said means being responsive to a given degree in excess of the motors, of regulating means "for onererequired ultimate degree of responselthere'of and being automatically readjustable after such response thereof I to compensate for such excess.

6. The combination with a plurality of sponsive to varying degrees upon different variations in the relative speeds of said motors to insure operation of the motor controlled thereby substantially in ,synchro- 'nism with another, said means being always responsive to a definite degreein excess of theulti natedegree of regulation required for any given speed variation of said motors and being automatically readjusta ble after response thereof to compensate for such excess.

7. The combination-with a plurality of motors, of regulating resistance for one and means responsive to a variation in the relative speeds of sald motors to ofiset the same by regulatlon of sald reslstance, said means being active automatically after each re-' sponse thereof 'to eflect adefinite curtailment of the resistance regulation accomplished thereby.

8. The combination with a plurality of motors, of regulating resistance for one and means responsive to variations in the rela-.

a given gross adjustment and a given net ad ustment for a, given speed variation and being active automatically upon gross adjustment to effect net adjustment thereof.

10. The combination with a plurality of motors, of electro-responsive regulating means for one adapted upon energization for 4 a given period to effect a given degree of regulation and upon deenergization to ourtail such degree of regulation but only to a. limited extent and means to energize'said electro-responsive means upon variations in the relative speeds of said motors.

ll. Theicombination with a plurality of motors, of electro-responsive regulating means for one adapted upon energization to-effect varying degrees of regulation according to the duration of its energization and upon deenergiZation-to effect a definite but only partial curtailment of its regulative tendency incident to suchresponse and means to energize said electro-responsive means upon variations'in the relative speeds of said motors and for periods varying with the speed variations. j

12. In a motor controller, the combination withla movable resistance controlling member, of a retarding device therefor and an operative connection therebetween permitting a predetermined range of resistance varying movement of said member inde-' .pendently' of said retarding device, said member when released being returnable automatically through a range equal to the aforesaid range.

13. In a motor controller, the combination with a resistance controlling member movable in opposite directions, a device to retard reverse movements of said member, an operative connection therebetween permitting a predetermined range of resistance varying movement of said member in either direction independently of said retarding device and biasing'means for said member to retract the same through a range equal to the aforesaid range when said member is released. V

14. In a motor controller, the combination with a resistancecontrolling. member movable in opposite directions, a double acting dash-pot and a lost motion connection therebetween including means biasing the former relatively to the latter whereby said member is permitted a limited play independently of said dash-pot when the former is moved in either direction and whereby said member when released is retracted tlwough a range equal to suchjplay.

15. In a motor controller, the combination with a resistance controlling member, an electro-responslve device to operate said member to Varying degrees andto thereupon release the same and means whereby said member is insured a definite but only partial return movement when the same is released after a given degree of movement thereof.

16. In a motor controller, the combination with a resistance controlling member, an

electro-resp'onsive device to operate said member to varying degrees and to thereupon release the same, and means for retarding movement of said member by said device-but permitting a limited movement of said member thereby prior to retardation thereof, said member when released being permitted a limited return movement equal to its afore said movement independently of said retarding means.

17. In a motor controller, the combination with a resistance controlling member, of electro responsive means for moving said -member to varying degrees in opposite directions and thereupon releasing the same,

means for retarding movement of said memher in opposite directions but permitting a limited play of the latter independently thereof and biasing means. for said member dividing such play for reverse movements thereof and for retracting said member to an equal degree when the same is released after operation thereof.

' 18. In combination, a motor, a movable resistance controlling member. for r'egulating the same, a retarding device for said member and an'operative connection between saldfdevlceand sald member permittlng a predetermined range of, resistance varying movement of said member independently of said retarding device, said member when released being returnable automatically through a, range equal tothe aforesaid range.

.19. In combination, a motor, a resistance controlling member movable in opposite directions for regulating the same, a device, to

retard reverse movements of said member,

an operative connection between said device and said member permitting a predetermined range fof resistance varying movement of saidmember in, either direction. independently of said retarding device and biasing means for said member to retract the same through a'range equal to theaforesaid range when said member is released.

erections for regulating the same, a double 20. In combination, a motor, ajresistance controlllng member movable 1n opposlte d1- acting dash pot and a lost motion connection between said member and said dash pot including means biasing the former 'relatively to the latter whereby said member is permitted a limited'play independently of said dash pot when the former is moved in either direction and whereby saidmemher when released is retracted through a range equal to such play.

21.- In combination, a motor, a resistance controlling member forregul'ating the Same, an electro-responsive device'to operate said member to varying degrees and to thereupon release the same and means whereby said member is insured a definite but only partial return movement when the same-'is released after a given degree of movement thereof. I v

22. In comblnation, a motor, ares stance controlling member for'regulating the same, v a

an electro-responsive device to operate said member to varying degrees and to thereupon rections and thereupon releasing the same, means' for retarding movement of said member. 1n opposite jdHGOtIOIISbUt permitting a limited play of the latter independently thereof and biasing means fors'aid member dividing such play. for reverse movements thereof and for retracting said member to an equal degree when the same .is released after operation thereofr r i In Witness whereof I: have hereunto subscribed my name. i

- ALBERT J. HORTON. 

